package com.gtw.modules.wx2.modules.util;

import java.security.MessageDigest;

import com.gtw.modules.wx2.modules.constant.SystemConstant;
import org.apache.commons.lang3.StringUtils;


/**
 * MD5加密工具类
 * 
 * @author phil
 * @date 2017年7月2日
 *
 */
public class MD5Util {

	private static final String hexDigits[] = { "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "a", "b", "c", "d",
			"e", "f" };

	private static String byteArrayToHexString(byte b[]) {
		StringBuffer buffer = new StringBuffer();
		for (int i = 0; i < b.length; i++) {
			buffer.append(byteToHexString(b[i]));
		}
		return buffer.toString();
	}

	private static String byteToHexString(byte b) {
		int n = b;
		if (n < 0) {
			n += 256;
		}
		int d1 = n / 16;
		int d2 = n % 16;
		return hexDigits[d1] + hexDigits[d2];
	}

	public static String MD5Encode(String origin, String charsetname) {
		String resultString = null;
		try {
			resultString = new String(origin);
			MessageDigest md = MessageDigest.getInstance("MD5");
			if(StringUtils.isEmpty(charsetname)) {
				resultString = byteArrayToHexString(md.digest(resultString.getBytes(SystemConstant.DEFAULT_CHARACTER_ENCODING)));
			} else {
				resultString = byteArrayToHexString(md.digest(resultString.getBytes(charsetname)));
			}
		} catch (Exception exception) {
			
		}
		return resultString;
	}

	public static void main(String args[]) {
		System.out.println(MD5Encode("ceshi", "gbk"));
		System.out.println(MD5Encode("ceshi", "utf-8"));
	}
}
